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Effects of p,p'-DDE exposure on gonadal development and gene expression in Japanese medaka(Oryzias latipes)

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Journal of Environmental Sciences 2008年第3期20卷 347-352页

作者： ZHANG Zhaobin hu jianying College of Environmental Sciences Peking University Beijing 100871 China

Although 1,1-dichloro-2,2-bis（p-chlorophenyl）-ethylene （p,p′-DDE）, the major and most persistent metabolite of dichlorodiphenyltrichloroethane （DDT）, was continually detected in wild fishes that showed abnormal gonad development such as intersex, little is known about the impact of p,p′-DDE exposure on gonad development in fishes. To survey the effects of p,p′-DDE on gonadal development and gene expressions, male juvenile （20-d post hatch） Japanese medaka （Oryzias latipes） was exposed to 1, 5, 20, and 100 μg/L p,p′-DDE for two months. Increased hepatosomatic index （HSI） and decreased gonadosomatic index （GSI） were found in the p,p′-DDE-treated groups. Intersex was found in 100 μg/L p,p′-DDE exposure group, as well as 100 ng/L 17α-ethynylestradiol （EE2） group. By quantitative real-time RT-PCR, it was found that gene expressions of vitellogenins （VTG-1, VTG-2）, choriogenins （CHG-H, CHG-L）, and estrogen receptor α （ER-α） in the liver of the fish were significantly up-regulated by p,p′-DDE exposure. VTG-1 and VTG- 2 were recommended as the preferred biomarker for assessing anti-androgenic p,p′-DDE because they were the highest up-regulated among the genes and showed good dose-response relationship. The up-regulated ER-α suggested that a potential synergetic effect would occur when p,p′-DDE coexists with other ER-α-binding endocrine-disrupting chemicals （EDCs）.

关键词： p,p′-DDE intersex vitellogenin quantitative real-time RT-PCR Oryzias latipes

双作用斯特林热机内部气体微团运行机理数值研究

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太阳能学报 2024年第6期45卷 389-395页

作者：常德鹏孙岩雷王珏罗靖胡剑英罗二仓中国科学院理化技术研究所低温科学与技术重点实验室北京100190 中国科学院大学工程科学学院北京100049 航天科工空间工程发展有限公司北京100854

针对一台双作用斯特林热机,通过SAGE计算以及Runge-Kutta法和线性插值等后处理过程,对内部气体微团进行热力求解,最终得到由欧拉观点转化为拉格朗日观点的热力结果。研究表明,斯特林热机回热器内部各气体微团独自运行于不同的热力过程,... 详细信息

针对一台双作用斯特林热机,通过SAGE计算以及Runge-Kutta法和线性插值等后处理过程,对内部气体微团进行热力求解,最终得到由欧拉观点转化为拉格朗日观点的热力结果。研究表明,斯特林热机回热器内部各气体微团独自运行于不同的热力过程,气体微团间互相接力,实现宏观上发动机的热功转换功能,其热力循环的包络线近似于2个等压过程和2个等温过程的组合。同时,研究实际机型的气体微团运行机理和热力过程,并从数值上验证斯特林循环与概括性卡诺循环的相互关系,为斯特林热机的设计与分析提供一定的理论基础。

关键词：斯特林热机斯特林循环 Runge-Kutta法运行机理概括性卡诺循环

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电驱动自由活塞斯特林热泵性能实验研究

工程热物理学报 2024年第9期45卷 2558-2564页

作者：王日颖胡剑英吴张华张丽敏贾子龙罗二仓中国科学院理化技术研究所低温工程学重点实验室北京100190 中国科学院大学北京100049

热泵供暖技术能够有效减少燃煤取暖产生的能源消耗和环境污染,但目前常用的热泵供暖系统的低温适应性较差,难以满足寒冷地区的供暖需求。考虑到斯特林热泵技术具有十分广泛的可用温区,本文研制了一台电驱动自由活塞斯特林空气源热泵,旨... 详细信息

热泵供暖技术能够有效减少燃煤取暖产生的能源消耗和环境污染,但目前常用的热泵供暖系统的低温适应性较差,难以满足寒冷地区的供暖需求。考虑到斯特林热泵技术具有十分广泛的可用温区,本文研制了一台电驱动自由活塞斯特林空气源热泵,旨在考察其在不同气候条件下的供热性能。实验结果表明,在普通、寒冷和极寒地区供暖工况下,电驱动自由活塞斯特林热泵的整机制热性能系数分别达到了2.31、1.97和1.78。随泵热温差增大,斯特林热泵的相对卡诺效率逐渐升高,其在大泵热温差下优势更加明显。

关键词：自由活塞斯特林热泵电驱动

Thermally controlled large deformation in temperaturesensitive hydrogels bilayers

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International Journal of Smart and Nano Materials 2021年第4期12卷 450-471页

作者： jianying hu Nan Jiang Jianke Du Department of Mechanics and Engineering Science Smart Materials and Advanced Structure LaboratorySchool of Mechanical Engineering and MechanicsNingbo UniversityNingboChina State Key Laboratory for Strength and Vibration of Mechanical Structures Xi’an Jiaotong UniversityXi’anChina

The present work investigates the thermally controlled deformation characteristics in temperature-sensitive hydrogels *** free energy density for temperature-sensitive hydrogels is modified,upon which the finite element model is developed and implemented through user-defined material subroutine UHYPER in the commercial software *** modified UHYPER implementation allows for more vividly depicting the continuous deformation in phase temperature region for temperature-sensitive *** thermally controlled cases of temperature-sensitive hydrogel including grippers,self-folding boxes,thermally driven origami are presented to illustrate a wide array of complex interesting applications or ***,we develop a simple model to theoretically calculate the bending angle of the temperature-sensitive hydrogel bilayers,which has been validated by the finite element simulation *** study can provide more insights for optimal design in thermally controlled hydrogels structures.

关键词： Temperature-sensitive hydrogels thermally controlled deformation swelling-induced bending

Determination of N-nitrosodimethylamine in drinking water by UPLC-MS/MS

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Journal of Environmental Sciences 2010年第10期22卷 1508-1512页

作者： Wanfeng Wang jianying hu Jianwei Yu Min Yang . State Key Lab of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. College of Environmental Science Peking University Beijing 100871 China

The method for detecting N-nitrosodimethylamine （NDMA） in drinking water using ultra performance liquid chromatography （UPLC） coupled with tandem mass spectrometry （MS/MS） was improved by optimizing the clean-up procedure to remove the matrix interference in pretreatment process, and was then applied to a survey of NDMA in both raw and finished water samples from five water treatment plants in South China. The NDMA concentrations ranged from 4.7 to 15.1 ng/L in raw water samples, and from 4.68 to 46.9 ng/L in finished water. The NDMA concentration in raw water was found to be related with nitrite concentration, and during the treatment, the NDMA concentration increased following ozonation but decreased after subsequent activated carbon treatment.

关键词： drinking water N-nitrosodimethylamine UPLC-MS/MS the matrix interference

Occurrence of sulfonamide antibiotics in sewage treatment plants

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Chinese Science Bulletin 2008年第4期53卷 514-520页

作者： CHANG Hong hu jianying WANG LeZheng SHAO Bing College of Environmental Sciences Peking University Beijing 100871 China Beijing Center for Disease Prevention and Control Beijing 100013 China

The occurrence of sulfonamide antibiotics(SAs) was investigated in the six sewage treatment plants(STPs) of Beijing,*** the 13 objective antibiotics,sulfamethoxazole,sulfapyridine,sulfamerazine,sulfadiazine and sulfamethizol were detected in the influents with the average concentrations of 1.2 ± 0.45,0.29 ± 0.25,0.048 ± 0.012,0.35 ± 0.52 and 0.33 ± 0.21 μg·L-1,respectively,and those in the effluents were 1.4 ± 0.74,0.22 ± 0.19,0.021 ± 0.008,0.22 ± 0.21and 0.01± 0 μg·L-1,*** was the predominant compound detected,and was found in all wastewater samples with the other two compounds sulfapyridine and *** should be noted that sulfadiazine was first reported in wastewaters,and the concentration levels of all detected compounds except for sulfamethizol(detected once in the effluent samples) in the influents were observed to be similar to those in the *** the data in this study,it can be found that sulfamethoxazole,sulfapyridine,sulfamerazine and sulfadiazine could be partly removed in anoxic and aerobic treatment unit and vice versa in anaerobic process,which led to their low or even negative removal rates in the *** increase on the concentrations of sulfamethoxazole and sulfapyridine in the effluents was found probably due to the biotransformation of their acetylated forms in anaerobic treatment *** addition,it was observed that the biodegradation of sulfamethoxazole and sulfapyridine could partly occur during the anoxic and aerobic process,while sulfamerazine was partly eliminated in the anaerobic and anoxic units.

关键词：污水处理生物转化城市污水处理厂磺胺类药抗生素

An acoustical pump capable of significantly increasing pressure ratio of thermoacoustic heat engines

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Chinese Science Bulletin 2006年第8期51卷 1014-1016页

作者： LUO Ercang hu jianying DAI Wei CHEN Yuanyuan Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China Graduate School of Chinese Academy of Sciences Beijing 100049 China

Pressure ratio is one of the important parameters for evaluating a thermoacoustic heat en- gine. A so-called acoustical pump, which is capable of significantly increasing pressure ratio of a ther- moacoustic heat engine, is proposed. Its operating principle is given. Also, a verification experiment is done with nitrogen gas in the energy-focused ther- moacoustic heat engine, showing that the pressure ratio increased from 1.25 to 1.47.

关键词：压力比声泵热力工程实验研究

A heat-driven thermoacoustic cryocooler capable of reaching below liquid hydrogen temperature

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Chinese Science Bulletin 2007年第4期52卷 574-576页

作者： hu jianying LUO ErCang DAI Wei Zhou Yuan Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

A "double-gas acoustic amplifier" is introduced to couple a thermoacoustic heat engine and a two-stage pulse tube cooler in this paper. Compared with previous acoustic amplifiers, this new acoustic amplifier maintains the function of amplification for pressure amplitude. In particular, the novel acoustic amplifier with a reservoir makes it possible to install an acoustic transparent but gas blocking elastic membrane between the engine and the cooler. Thus, the engine can use nitrogen as the working gas to work at low frequency; and meanwhile, the cooler can still use helium as the working gas to maintain its high performance. With this new amplifier, the cooling temperature of a two-stage pulse tube cooler driven by an energy-focused thermoacoustic engine reached 18.7 K.

关键词：热驱动热声制冷低温冷却器液氢温度声学放大器

A novel coupling configuration for thermoacoustically-driven pulse tube coolers: Acoustic amplifier

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Chinese Science Bulletin 2005年第18期50卷 2112-2114页

作者： DAI Wei LUO Ercang hu jianying CHEN Yanyan Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing 100080 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

Thermoacoustically-driven pulse tube cooler can provide cryogenic cooling power with no moving com-ponents. Up to now, pulse tube cooler is directly coupled with the thermoacoustic engine and obtainable pressure ratio for the pulse tube cooler is limited by the capability of the ther-moacoustic engine. The authors propose here the concept of acoustic amplifier, which is actually a long tube connecting the engine with the pulse tube cooler. Theoretical calculation shows that suitable length and diameter of the tube can lead to a pressure wave amplification effect which means that pressure wave amplitude coming from the thermoacoustic engine can be much amplified to drive the pulse tube cooler. Based on this, a 2.8 m long copper tube with 8 mm inner diameter is used as the acoustic amplifier in experiments. The experimental results show that due to the amplification effect, pressure wave amplitude at the inlet of the pulse tube cooler is over 2.5 times of that at the engine outlet. Typically, with 1.67 kW heating power, the pressure ratio provided by the engine is 1.11 while at the inlet of the pulse tube cooler the pressure ratio is 1.32, which leads to a lowest no-load temperature of 65.7 K.

关键词：声音放大器脉冲管冷却器压力波